>What is important here is that, where ISO doesn't provide a code, that
>users do have some other source of codes for internal and, more
>importantly, interchange purposes. Many independent agencies and
>individuals are already using Ethnologue codes in this way precisely
>because ISO provides very limited coverage.

I agree. For example when it was brought up that other Turkic languages
might be using the dot less i. I noticed that the SIL confirmed that
Azerbaijan uses the Latin alphabet. On the other hand it said that Urum was
"Spoken by ethnic 'Greeks'". Unless this is some kind of inside joke I can
not imagine any Greek having anything to do with anything Turkish.

I was proposing using the SIL codes to supplement the ISO codes rather than
the IANA codes.